adb - I can't find the boot/recovery partitions on my Android phone for backup - where are they?

I'm trying to back up boot.img, recovery.img, and system.img on my Android phone. I've found several mentions of running this command:

cat proc/mtd

and then just using dd to copy the listed mount points. Seems straightforward enough. Unfortunately, the output of that command is just this single line:

dev:    size   erasesize  name

df also doesn't list the usual "Mounted On" column, just the filesystem. This is the output of df:

Filesystem             Size   Used   Free   Blksize
/dev                   234M    52K   234M   4096
/mnt/secure            234M     0K   234M   4096
/mnt/asec              234M     0K   234M   4096
/mnt/obb               234M     0K   234M   4096
/system                640M   459M   180M   4096
/data                    1G   406M   898M   4096
/cache                 369M     6M   363M   4096
/protect_f               8M     4M     4M   4096
/protect_s               8M     4M     4M   4096

/mnt/cd-rom              1M     1M     0K   2048
/storage/sdcard1         1G    24M     1G   16384
/storage/sdcard0         7G     2G     5G   32768
/mnt/secure/asec         7G     2G     5G   32768

Some details about my phone:

• It's a BLU ADVANCE 4.0


• Board is Mediatek MT6572


• Android version is 4.2.2



• Kernel version is 3.4.5


• I do have root access

So, to reiterate my question - where are the partitions? How can I find them?

While I'm not necessarily averse to using programs other than the shell it seems like I really should be able to do this from there.

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EDIT: I used dd on the various mmcblk files I found in /dev/block. Most of them I terminated prematurely as they were 100MiB+, but two (mmcblk0p2 and mmcblk0p3) came out to about 10MiB each which seems more probable for boot and recovery. The contents of these when mounted are:

• a directory labelled lost+found (ext?)


• a directory labelled md, the subcontents of which differ

In mmcblk0p2 the contents of md are:

• Two files of unknown type, one 4B one 2.0KiB, labelled MPOD_000 and ST33A004 respectively

In mmcblk0p3 the contents of md are:

• One file of unknown type, 2.0KiB, labelled ST33B004